Stars: Birth, Life, Death

How gas and dust clouds turn into thermonuclear reactors, and then into white dwarfs, neutron stars, or black holes. This course breaks down the life cycle of stars in detail: from gravitational collapse of protostars to the final outbursts of supernovae. Understanding stellar evolution is key to interpreting observational astronomy, from spectral classes to the Hertzsprung–Russell diagram, and is necessary for reading astrophysics research papers and news meaningfully. The program covers the full cycle: mechanisms of star formation in molecular clouds, conditions for igniting thermonuclear reactions, evolution on the main sequence depending on mass and chemical composition. You will learn how stars transition to the red giant phase, why massive stars explode as Type II supernovae, and how low-mass stars shed their envelopes, forming planetary nebulae. The course examines end states in detail: white dwarfs, neutron stars, and black holes, including their observational manifestations—pulsars, accretion disks, and gravitational waves. Special attention is given to spectral classification and reading diagrams that allow you to determine a star’s age and evolutionary stage. The course methodology is based on analysis of real astrophysical data: you will learn to interpret spectra, Hertzsprung–Russell diagrams, and light curves. Typical mistakes are covered—for example, confusing the evolution of stars of different masses or misidentifying evolutionary stages by color. A practical emphasis is placed on the link between mass and composition with lifespan and a star’s final outcome, enabling you to predict the evolution of specific objects, including the Sun. The course is intended for students and graduates of physics and mathematics programs, beginner amateur astronomers with basic physics knowledge, astronomy teachers who want to deepen their understanding of stellar evolution, as well as scientific journalists and science communicators who need an accurate conceptual framework to describe astrophysical processes. By the end of the course, you will be able to confidently describe all stages of stellar evolution, from protostar to compact remnant, using correct terminology. You will understand how to determine a star’s mass, age, and evolutionary stage from its spectrum and position on the diagram, and how to explain why the Sun, after several billion years, will become a red giant and then a white dwarf. The knowledge gained will let you independently analyze science popularization articles and astrophysics lectures.